2.5 has code 33

[lpeters]

My 1989 chevy 2.5 has a code 33 that I cant figure out. I have TP giving me good info (Thanks to Robert). I Found the fuel pressure was 4lbs over the 13 # max and the tps was out of bounds. replaced the tps and the fuel regulator. Runs a lot better now. while idling, I get 38.13 map load and 4.78 map volts. The vac sensor has 2.8 volts. Rich/lean says rich. I have new map, replaced all vac hoes and the darn code is still there.(cleared codes with battery disconnect) Could someone give me steps they would take from here. Thanks.

[EagleMark]

I get 38.13 map load and 4.78 map volts.

MAP kpa of 38.xx at idle seems fine but that should be around 1.5v... MAP volts 4.78v is like 100 MAP kpa or WOT.

Something is wrong there?

[robertisaar]

hmm..... i wonder if MAP is showing the defaulted(estimated) value?

[lpeters]

OK guys, That got me to thinking. ran the engine to 2000 RPM to see what happens. TPS = .92 volts
o2 = 1012.18
MAP = 2.39 volts
VAC sensor - 2.98 volts
70 degrees here and raining
4.80 barometric
I am getting a error 33 Map high and 45 o2 rich.

Now I am totally confused. shouldn't TPS get higher with more throttle?

[lpeters]

Found the problem! After many bottles of advil, I found that the vacuum hole in the carb plate was stopped up. After blowing it out, soaking it in carb bath and going to the witch doctor down on the bayou, no vac. After finding no matches in the junk yard, I started to think of a way around this. My fix was to get a small adjustable valve, put a T fitting in and borrow the vacuum from the a/c that closes the vents. Started the engine and slowly closed the valve till I got 18 lbs vac it was looking for. reset the codes by disconnecting the battery and no more bad idle or check engine light. When I find a TB for replacement, I will put it all back.